Bilirubin_oxidase
In enzymology, a bilirubin oxidase, BOD or BOx, (EC 1.3.3.5) is an enzyme encoded by a gene in various organisms that catalyzes the chemical reaction
- 2 bilirubin + O2 2 biliverdin + 2 H2O
This enzyme belongs to the family of oxidoreductases, to be specific those acting on the CH-CH group of donor with oxygen as acceptor. The systematic name of this enzyme class is bilirubin:oxygen oxidoreductase. This enzyme is also called bilirubin oxidase M-1. This enzyme participates in porphyrin and chlorophyll metabolism. It is widely studied as a catalyst for oxygen reduction.[1]
Two structures of bilirubin oxidase from the ascomycete Myrothecium verrucaria have been deposited in the Protein Data Bank (accession codes 3abg and 2xll).[2][3]
The active site consists of four copper centers, reminiscent of laccase. These centers are classified as type I (cys, met, his, his), type II (3his), and two type III (2his).[4] The latter two centers are arranged in a trinuclear copper cluster forming the active site for oxygen reduction.[5] The type I copper center is the primary electron acceptor and the site for the reduction of bilirubin.